A new type of composite nanoparticles (CNPs) was prepared by loading a typical inhibitor 1-hydroxybenzotriazole (HOBT) for corrosion protection of copper alloy in mesoporous silica nano-containers. The release kinetics of HOBT from CNPs in 3.5% NaCl solution was in conformity with the first order kinetic model. The open circuit potential monitoring, the morphology observation and the scanning Kelvin probe measurement of the Cu-Zn alloy in 3.5% NaCl solution with CNPs proved that a uniformly protective film was formed on the surface. Electrochemical impedance spectroscopy was employed to analyse the corrosion inhibition process of CNPs on the Cu-Zn alloy.